/*
 * Copyright (C) 2011 Reeny
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package de.tobidodo.spritmonclient.util;

import java.io.IOException;

import org.apache.http.HttpException;
import org.apache.http.HttpHost;
import org.apache.http.HttpRequest;
import org.apache.http.HttpRequestInterceptor;
import org.apache.http.auth.AuthScope;
import org.apache.http.auth.AuthState;
import org.apache.http.auth.Credentials;
import org.apache.http.client.CredentialsProvider;
import org.apache.http.client.protocol.ClientContext;
import org.apache.http.impl.auth.BasicScheme;
import org.apache.http.protocol.ExecutionContext;
import org.apache.http.protocol.HttpContext;

public class PreemptiveAuthentication implements HttpRequestInterceptor {

	@Override
	public void process(final HttpRequest request, final HttpContext context) throws HttpException, IOException {
		AuthState authState = (AuthState) context.getAttribute(ClientContext.TARGET_AUTH_STATE);
		CredentialsProvider credsProvider = (CredentialsProvider) context.getAttribute(ClientContext.CREDS_PROVIDER);
		HttpHost targetHost = (HttpHost) context.getAttribute(ExecutionContext.HTTP_TARGET_HOST);

		if (authState.getAuthScheme() == null) {
			AuthScope authScope = new AuthScope(targetHost.getHostName(), targetHost.getPort());
			Credentials creds = credsProvider.getCredentials(authScope);
			if (creds != null) {
				authState.setAuthScheme(new BasicScheme());
				authState.setCredentials(creds);
			}
		}
	}   

}
